Laser Particle Size AnalyzerAs one of the widely used testing instruments in the field of powders, the range can almost achieve full coverage of particle testing from 20 nanometers to 3500 micrometers. However, due to the uneven theoretical understanding and report interpretation level of operators, as well as the large number of instrument brands and models leading to differences in data comparison, these often lead to misunderstandings among testing personnel in actual research and development production.

Recently, Dr. Zhang Fugen, a scientist from Truth Optics, held an online live broadcast on particle testing to meet the needs of powder workers. He discussed the selection and use of laser particle size analysis instruments and answered questions for industry users.

The following are the main contents of online live streaming, including:

① It is believed that the measurement lower limit of laser particle size analyzer can reach 10nm;

② It is believed that Dmax (or D100) and Dmin (or D0) in the laser particle size testing report represent the particles and small particles in the sample, respectively;

③ Expressing the particle size distribution data of the sample using quantity distribution;

④ When inputting measurement parameters, even if the sample does not absorb optically, an absorption coefficient should be added;

⑤ Imported laser particle size analyzers are more advanced than domestically produced ones;

⑥ The measurement results output by laser particle size analyzers, especially imported ones, are the true particle size distribution;

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This online live streaming event received the participation and interaction of many professionals in the powder industry, among whom many netizens raised their own questions in the comment section. Dr. Zhang provided detailed answers to these questions one by one after the report, and received everyone's approval. The editor has compiled the questions raised by everyone as follows. Interested viewers canClick here to access and watch live video replayIf you have similar questions, please feel free to contact us directly.

Attachment: Interactive Questions

1. Is there a correlation between the data detected by different specifications and models of laser particle size analyzers? Can they be converted to each other. Otherwise, the difference in powder particle size data between suppliers and customers due to the use of different instruments will result in ineffective quality control?
2. Will the measured particle size result in different particle densities?
3. Do we need two devices, a laser particle size analyzer and dynamic light scattering, to provide reasonable results for samples with a wide particle size distribution below 100nm?
4. What should we do if we don't know what different substances have different refractive indices?
5. The reproducibility of particle size distribution is poor, and there are many tail differences. How to test it?
6. Which instrument is currently better for measuring the particle size distribution of flake aluminum powder?
7. Does the laser particle size analyzer need to be calibrated regularly? If necessary, how can I do it?
8. What is the difference between volume distribution and quantity distribution, and how are they converted?
9. The same substance, but from different manufacturers, has a certain difference in refractive index. So, when selecting parameters, how should the refractive index be chosen?
10. The ultrasonic vibrating screen passed through 800 mesh, while the laser particle size analyzer measured D90 to be 40 microns and D97 to be 60 microns. What could be the possible reason for such a large difference in results?
11. When measuring powders, under what circumstances should we choose volume integral and area integral?
12. The reproducibility of particle size distribution is poor, and there are many tail differences. How to test it?
13. Can the centrifugal settling particle size analyzer measure samples up to 50nm?
14. Does the laser particle size analyzer need to be calibrated regularly? If necessary, how can I do it?